Viewing the size of stack elements (AKA, where have all the bytes gone?)

Tariel Gogoberidze tariel at
Tue May 23 17:31:27 EDT 2006

On May 23, 2006, at 18:33:57 +0100,  Ben Rubinstein wrote:

> The kind of thing I'd like in an ideal world is something that would 
> be able
> to tell me the number of bytes in an (uncompressed, unencrypted) stack 
> file
> taken up by an object and then make it possible to drill down.  So a 
> stack
> file consists of I guess a header which occupies some number of bytes, 
> and a
> number of stacks each of which occupy some number of bytes.  Similarly 
> the
> size of a stack can presumably be broken down into a header, 
> properties (inc
> stack script), audioclips, videoclips, cards, and possibly groups?  
> Each of
> those values (apart from the header) can similarly be drilled down 
> into.
> Is there any available that would produce such a report, or the data 
> for it?
> If not, how difficult would it be? As far as I can tell, Transcript 
> doesn't
> expose much information: there is a "size" property, but according to 
> the docs
> it's only applicable to a few objects - and for stacks always returns 
> "10000".
>   I can iterate over properties and discover their size; but for, say, 
> a
> field, I don't know whether how the text is stored differs according 
> to eg how
> much of it is styled, whether it contains unicode elements, etc.  Also 
> there isn't even a way to iterate over the properties of an object (is 
> this
> right?) - 'the properties' according to the docs is not complete.

'the properties' is pretty much complete, I checked a while ago. The 
missing properties are either redundant  or introduced for HyperCard / 
SyperCard compatibility, like "Size" property you mentioned. For 
example, there is no height or width but "the rect" covers them both 
and same goes with "the colors" which returns 10 line description of 
all separate color properties)

So, you can try something like this..

on GetSizes
   repeat with j= 1 to number of controls
     put the effective properties of  control j into tPropArray
     combine  tPropArray using numToChar (24) and numToChar (25)
     put the short name of control j & " = " & number of chars of 
tPropArray & cr after tSizeList
     put tPropArray & numToChar (26) after tAllPropArray
   end repeat
   put number of chars of tAllPropArray & cr & tSizeList
   -- write tAllPropArray to file
end GetSizes

and  when used in reverse it recreates text styles of field as well  
(not sure about unicode stuff but you can check with "reverse" function 

on RestoreProps
   -- in new stack, read tAllPropArray from file
   lock messages
   lock screen
   set itemDel to numToChar (26)
   repeat with j= 1 to number of items of tAllPropArray
     put item j of  tAllPropArray into tPropArray
     split tPropArray using numToChar (24) and numToChar (25)
     put tPropArray ["ID"] into tID
     set the properties of control ID tID to tPropArray
     set the properties of control ID tID to tPropArray -- to overwrite 
auto settings
   end repeat
   unlock screen
   unlock messages
end RestoreProps

Of course all above would not account for custom properties,  audio / 
video clips etc but comparing original and "recreated" stack may give 
you some info you need.

I even use similar functions as UNDO engine for relatively small stacks 
but there is a catch. Some properties when set would trigger auto 
setting of another property so "recreation" should be done in two 
passes or in specific order.

best regards

More information about the use-livecode mailing list